Stringed musical instrument



Dec. 3, 1968 M. HELBOURNE STRINGED MUSICAL INSTRUMENT 2 Sheets-Sheet 1 Filed Oct. 19, 1964 LA Marga/'87 fla ing ATTOR/VErs Dec. 3, 1968 M. HELBOURNE STRINGED MUSICAL INSTRUMENT 2 Sheets-Sheet 2 Filed Oct. 19, 1964 8 H mw T 0 mm mH w W m m United States Patent 3,413,883 STRINGED MUSICAL INSTRUMENT Margaret Helbourne, 18443 Muirland, Detroit, Mich. 48221 Filed Oct. 19, 1964, Ser. No. 404,854 6 Claims. (Cl. 84267) ABSTRACT OF THE DISCLOSURE A practice guitar comprises a one-piece solid staff formed of wood and having a conventionally shaped head, head nut and finger board at one end. The finger board, fitted with conventional frets, is an integral part of the staff. In place of a conventional hollow sound box, the other end of the staff is extended to form the body of the staff with the body forming the sole acoustical base of the instrument when the instrument is completely assembled. An open wire frame in four parts and having the contour of a conventional sound box is removably secured to the staff. An adjustable lower bridge is mounted on the body to vary the position of the strings vertically, laterally or both, with the bridge being held firmly in the desired adjusted position when the strings are tensioned.

This invention relates to stringed musical instruments and in particular to a guitar particularly suited for practicing.

In a conventional guitar, an enlarged hollow sound box is joined to one end of a fretted neck having a head at its other end remote from the sound box. Strings are tunably secured at one end to the head and the other end of the strings are secured on the box remote from the neck so that the strings overlie a portion of the sound box. This portion of the sound box is perforated so that the sound box acts as a resonant chamber for sound waves produced by the strings. Guitars having this construction are capable of producing loud volume depending on the degree to which the strings are plucked. However, it is desirable to practice the plucking action for notes intended to be loud without producing the loud volume so as not to disturb or annoy other persons in the vicinity.

The objects of this invention are to provide a guitar that is constructed simply and economically; that produces notes that are true and of good quality at low volume; that is lightweight yet strong enough to accommodate high stress encountered in steel stringed guitars; and that can be readily disassembled into a compact unit.

In the drawings:

FIG. 1 is a perspective view of a guitar having a solid, one-piece staff constructed in accordance with the instant invention.

FIG. 2 is a top view of the guitar illustrated in FIG. 1.

FIG. 3 is a longitudinal section taken along line 33 of FIG. 2.

FIG. 4 is an enlarged perspective view illustrating a lower bridge on the staff that is vertically and laterally adjustable to vary the distances between the strings and the staff.

FIG. 4A is a fragmentary vertical section of the adjustable bridge illustrated in FIG. 4.

FIG. 5 illustrates a modification where the staff is severed and the severed portions are hinged so that the guitar can be collapsed.

FIG. 6 illustrates a modification wherein the guitar in FIG. 1 is provided with an audio pickup and a modified jazz bridge.

By way of illustration and not for purposes of limitation, FIG. 1 illustrates a guitar 10 constructed in accordance with the instant invention and having a solid, onepiece staff 12. Guitar 10, as illustrated in FIGS. 1-3, conforms generally to classical and flamenco guitar styling.

3,413,883 Patented Dec. 3, 1968 "ice However, the guitar may be constructed to conform with other guitar styles or types, such as jazz, popular, or folk. Staff 12 is fashioned with a head 14 joined to one end of an elongated neck 16 which has its other end joined to an enlarged body 18. Six strings 20 are mounted on staff 12 with one end of the strings tunably secured to head 14 and the other end of the strings fixedly secured to a bridge 22 adjustably mounted on staff 12. An open frame 24 is mounted on staff 12 to simulate the physical configuration of a conventional sound box. A flat rectangular plate 26 is mounted on staff 12 immediately adjacent bridge 22 so as to underlie the strings 20.

Staff 12 is formed from one solid piece of wood, preferably dense resonant wood such as mahogany or walnut, although metal or plastic can be used. Head 14 is provided with any suitable type of gearing 30 for tensioning and thereby tuning strings 20. The particular type of gearingf is chosen to correspond to the type or style of the guitar. By way of example, in a folk guitar the gearing 30 would be in the form of pegs frictionally held in head 14. The upper end of neck 16 adjacent head 14 is provided with a conventional head nut 32 which carries strings 20 on the outer face thereof. Head 14 is inclined downward from the adjacent end of neck 16 and nut 32 so that the force applied to the head from the tension in the strings 20 is distributed in such a way as to reduce the component of the force tending to how the staff. Neck 16 has a flat upper face 34 in which frets 36 are fixedly embedded to form a finger board integral with neck 16. Neck 16 has a hemispherical cross section of gradually increasing dimensions in a direction way from head 14 to correspond to the neck of a conventional guitar. Staff 12 is enlarged somewhat in depth as at 37 at the junction of neck 16 and body 18. Adjacent neck 16, body 18 is recessed along opposite longitudinal edges of its upper face as designated by numeral 38 to form a raised flat face 40 also having frets 36 embedded therein to extend the finger board of neck 16. As in a conventional guitar, the 12th fret is disposed above the juncture of neck 16 and body 18. At the lower end of face 40, remote from neck 16, body 18 is fashioned with a recess 42 having a curved lower side wall 44. Recess 42 simulates the sound hole of a conventional guitar.

Plate 26 is mounted between recess 42 and bridge 22 on a flat receded face 46. Face 46 extends downward, to the left as viewed in FIG. 3, beyond bridge 22 in a direction away from head 14. Plate 26, which may be made of rigid transparent plastic, gives the player the feel of a conventional sound box and also functions as a sounding board to some extent. Additionally, plate 26 is useful in playing flamenco music to produce audible tapping sounds when struck by the fingers. Frame 24 comprises two top wires 47 and two bottom wires 48 mounted in pairs to project outwardly from opposite sides of body 18. Wires 47, 48 are each bent to the configuration shown so that frame 24 has a contour corresponding to the contour of a conventional sound box. Wires 47 are secured to body 18 at opposite sides thereof by press-fitting opposite ends of each wire 47 into mating holes provided in body 18. Wires 48 are formed with right angled terminal portions 49 that are press-fitted into mating holes provided in the bottom of body 18. By securing wires 47, 48 to body 18 with a press fit, wires 47, 48 can be removed if desired. Other means for releasably securing wires 47, 48 to body 18 may be used where it is desired to remove the wires frequently.

Bridge 22 comprises a generally rectangular block 50 (FIGS. 4 and 4A) slidably mounted in a square recess 51 formed in bory 18. Block 50 has forward and trailing sides 52, 54, respectively, and a top 56. The thickness of block 50 between sides 52, 54 is dimensioned relative to the dimension of recess 52 such that block 50 fits closely and slidably into recess 51. A bridge nut 60 is fixedly mounted in block 50 at the top thereof to project upwardly from top 56 as viewed in FIG. 4. Top 56 is recessed as at 62 to form a mounting flange 64. Flange 64 has siX spaced perforations 66 through which the lower ends of strings are tied in a conventional manner. An internally threaded sleeve 68 is securely press-fitted into a vertical bore in block 50 from the bottom thereof. Sleeve 68 opens downwardly at the bottom face of block 50. A screw 70 extends upwardly as viewed in FIG. 4 through a suitable aperture 72 in body 18 and threadably engages in sleeve 68. A recess 73 is formed in body 18 at the bottom of recess 51 and at the top of aperture 72 to accommodate a snap ring 74 engaged in a circumferential groove in screw 70. Snap ring 74 and a head 76 on screw 70 are adapted to engage body 18 to limit ver tical movement of screw 70 but permit rotation thereof.

When the tension of the strings is relaxed by adjusting gearing and screw 70 is tightened, block is drawn downward to drop strings 20 closer to frets 36; and when screw 70 is loosened, block 50 is urged upward out of recess 51 to raise strings 20 away from frets 36, as viewed in FIG. 4. Furthermore, a lateral adjustment can be made simultaneously by tilting block 50 to either side as viewed in FIG. 4, within the free play permitted by screw 70. To this end, aperture 72 ha a diameter slightly greater than the diameter of screw 70 to provide a loose fit for screw 70. In this manner, the finger action which is determined by the distance of the strings from the frets can not only be adjusted vertically by raising or lowering all six strings uniformly, but also laterally, as tilting of the block permits the strings on one side of the neck to be raised or lowered more or less than those on the other side.

When strings 20 are tuned, block 50 is canted in a clockwise direction as viewed in FIG. 4A. The string tension urges the top of leading side 52 on block 50 firmly against a forward face 78 (FIG. 4A) of recess 51 and the bottom of trailing side 54 firmly against a trailing face 79 of recess 51 to fix block 50 firmly in the position selected by the user. All or substantially all of the string tension will be distributed to body 18 by engagement of face 78 with side 52 and face 79 with side 54. Depending on the closeness of the fit between block 50 and recess 51, some string tension may be distributed to body 18 through screw 70 although screw 70 is intended primarily to merely adjust the height of bridge 22. Conventional manufacturing tolerances will usually provide the minute play in block 50 necessary to achieve effective canting to hold block 50 firmly in place and also provide laterally tilting adjustability. Vertical and lateral adjustability is desirable not only for young or beginning students, whose practice instrument should have a finger action suitable to their individual and progressing muscular development, but also to advanced players or artists who can therewith recreate on their practice instrument the exact finger action characteristics to which they are accustomed.

FIG. 5 illustrates a modification of the practice guitar illustrated in FIG. 1 wherein stalf 12 is severed to form. an interface 80 and the severed halves of staff 12 are pivotly connected by a hinge 82. With the hinged construction, strings 20 may be removed from gears 30 and neck 16 can be folded downwardly under body 18 to collapse staff 12 into a compact unit. In this embodiment, wires 47 and 48 also have their ends releasably mounted on staff 12 so that wire 47 and 48 can be removed to provide a more compact unit. The surfaces of the severed halves at interface 80 are flat so as to mate properly, and are not finished with lacquer or other sealers that might impair the resonant qualities of staff 12.

FIG. 6 illustrates a further modification in the guitar 10 of FIG. 1 where the guitar is electrified by mounting an audio pickup 84 on staff 12 at the bottom. of recess 42 directly beneath strings 20. A plate 85, corresponding to plate 26 in FIGS. 1-3, is modified so that suitable controls for the audio pickup can be mounted thereon. Additionally, as shown in FIG. 6, a jazz guitar bridge 86 has an inclined nut 90 to more closely conform the guitar to jazz guitar styling. Except for nut 90, bridge 86 (FIG. 6) may be identical to bridge 22 (FIG. 4).

The guitar described hereinabove, constructed without a conventional hollow sound box or resonant cavity, produces true tones of good quality at low volume and can be manufactured economically.

I claim:

1. A stringed musical practice instrument for producing musical notes that are true and of good quality at low volume comprising a staff, said staff being formed with a head at one end, an elongated neck joined at one end to said head, and a body joined to the opposite end of said neck, strings, means on said body for securing one end of said strings to said body, the other ends of said strings being operatively secured to said head, said body having an upper face thereon underlying said strings, said face being substantially imperforate and said body having a configuration other than the configuration of a guitar or the like such that said body does not function as a conventional, perforated sound box, said body further comprises the sole acoustical base of said instrument when said instrument is completely assembled, and an open contoured frame mounted on said staff, said frame comprising wire-like members projecting laterally outwardly from said staff and shaped to simulate the configuration of a sound box of a guitar and the like, said frame being open at the top, bottom and sides thereof when said instrument is completely assembled.

2. The instrument set forth in claim 1 wherein said frame comprises two pairs of wires, one pair of wires projecting in a direction laterally outwardly from one side of said staff and the other pair of wires projecting in a direction laterally outwardly from the opposite side of said staff and wherein said wires are releasably mounted on said staff for assembly and disassembly therewith.

3. A stringed musical instrument having a head at one end for tunably securing one end of said strings to said instrument, means for adjustably securing the other end of said strings to said instrument adjacent the other end of said instrument remote from said head comprising means on said instrument forming a recess, said recess having a pair of spaced side walls, a bridge disposed in said recess and having side walls dimensioned to fit slidably but closely with an adjacent one of said side walls of said recess, said other end of said strings being secured to said bridge so that when said strings are loosened, the position of said bridge in said recess may be adjusted and when said strings are tuned, the tension in said strings cants said bridge to bring said side walls of said bridge into engagement with adjacent side walls of said recess to hold said bridge in place.

4. The instrument set forth in claim 3 further comprising an adjustable fastener interconnecting said bridge and said instrument to secure said bridge at selected heights in said recess.

5. The instrument set forth in claim 4 wherein said fastener comprises an internally threaded sleeve fixedly mounted in said bridge and opening at the bottom of said bridge, an aperture in said recess forming means opening at the bottom of said recess and registering with said sleeve, a screw passing through said aperture and threadably engaging said sleeve, said screw being'rotatable in said aperture, means interengaging with said screw and said instrument for restraining longitudinal movement of said screw whereby when tension in said strings is relaxed, said fastener may be rotated in one direction to urge said bridge in a direction out of said recess and rotated in the opposite direction to draw said bridge in a direction into said recess so that when tension is restored to said strings, said bridge will be urged into tight frictional engagement wtih said side walls of said recess to hold said bridge firmly in the adjusted position.

5 6. The combination set forth in claim 5 wherein said 3,072,007 aperture has a diameter sufiiciently greater than said 3,130,625 screw so as to permit lateral tilting of said bridge in said 3,204,510 recess when the tension in said strings is releaxed.

5 References Cited 516 455 UNITED STATES PATENTS 1,081,296

1,611,563 12/1926 Rothman 84-267 2,905,042 9/ 1956 Hoyer 84-298 1/1963 Burke 84-267 4/1964 Savona 84-267 9/ 1965 Hopf 84-291 FOREIGN PATENTS 2/ 1955 Italy.

5/ 1960 Germany.

RICHARD B. WILKINSON, Primary Examiner.

2,956,467 10/1960 Toop 84-267 10 GARY M. POLUMBUS, Assistant Examiner. 

